Which choice avoids run-on sentences to present the information clearly and correctly?

a.)levi wanted to save the endangered sparrows, he built a birdhouse and he passed out flyers and he also hung signs to tell people to keep their cats inside.

b.)levi wanted to save the endangered sparrows. he built a birdhouse, and he passed out flyers. he also hung signs to tell people to keep their cats inside.

c.)levi wanted to save the endangered sparrows. he built a birdhouse, and he passed out flyers he also hung signs to tell people to keep their cats inside.

d.)levi wanted to save the endangered sparrows, so he built a birdhouse. he passed out flyers, he also hung signs to tell people to keep their cats inside.